How does negative feedback regulate thyroxine?
Answer and explanation
Correct answer: B. High thyroxine reduces TSH release so thyroxine output falls
- Step 1: The pituitary releases TSH to stimulate the thyroid. Step 2. Rising thyroxine inhibits TSH secretion, lowering output back to the set point. Answer: High thyroxine reduces TSH release so thyroxine output falls. Why not the others: Positive feedback would amplify the change; low thyroxine should raise TSH.
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